I have used my son's M4gery a few seasons in the local military matches.
First season when it needed breaking in.
Another season he replaced the fire control group with one less prone to unexpected bump fire.
In prepping the gun I did what I customarily do with blowback .22 rifles or my M1 carbine.
_ Clean, leave a light sheen of oil over all - the amount left when wiped with a slightly oily cloth after cleaning.
_ Bolt and receiver exposed directly to gas, left clean and dry.
_ Painted a quality lubricating oil on all bolt and receiver parts showing metal to metal contact.
Upper East Tennessee, the only dirt in the action would be powder fouling. Not a lot of airborne dust or sand.
Last season I shot his M4gery I thoroughly cleaned and lubed the gun before the first match. I did not clean the action between matches. I thoroughly cleaned it at the end of the season. Not an outstandingly high round count, 7 matches each 20 rounds for score, sighting rounds, and my tests to make sure the new trigger group would not double even if held loosely. No malfunctions. Contradicted what I had been told, to clean an Armalite as immediately as possible or at least pour CLP in the action.
I am prejudiced against running any autoloader wet. Excess oil and wood stocks are not compatible. I have been indoctrinated that excess lube is a dirt and dust magnet and carries fouling sludge into places not reached by ordinary cleaning. In WWII my Dad used the BAR. He liked the semi- or full- selector version, but did not like the variable rate version, slow auto or fast auto selector. The slow auto damper was built into the sealed area of the recoil spring assembly inaccesible to the user, and if gummed up, it had to be serviced by the unit armourer.
Friends with combat experience with the ArmaLite family swear by running ARs wet, at least if you are in a situation where you can't clean the gun properly, you can at least squirt some CLP in there and keep it running. Personally I hope to avoid prolonged firefights, but the advice is useful to keep in mind. Still I am not sold on running wet.